关键词: 微细尾砂, 水泥, 净浆流动度, 絮网结构, 超塑化剂

Abstract: Total tailings paste cemented backfill is a necessary choice of developing underground mining with environmentally friendly and resource efficient use of type.In order to resolve the problem of the fluidity and concentration fall of total tailings paste produced by refined tailings，effect of polycarboxylate and naphthalene sulfonate superplasticizers on the fluidity of cement and microfine tailings slurry was explored and the microscopic analysis of the flocculation structure of the test samples was carried out.The test results showed that polycarboxylate superplasticizer greatly increased the fluidity of cement and microfine tailings slurry，and naphthalene sulfonate superplasticizer also obviously increased the fluidity of cement slurry but less increased the fluidity of microfine tailings slurry.The cement slurry and microfine tailings slurry without superplasticizers had similar flocculation structures observed by microscope，and the flocculation structures of tailings slurry were smaller and their bond force was stronger because of finer particle size of tailings compared with cement slurry.polycarboxylate superplasticizer based on steric hindrance effect could break flocculation structures with strong bond and released more free water to increase slurry fluidity in comparison with naphthalene sulfonate superplasticizer based on electrostatic repulsion force effect.So，the conclusion is that polycarboxylate superplasticizer will be a potential excellent admixture in preparing total tailing paste cemented backfill slurry.

Key words: Microfine tailings, Cement, Slurry fluidity, Flocculation structure, Superplasticizers